Microchannel devices and systems have various applications that utilize the fluid properties in small cross-sectional dimensioned conduits. These small conduits can be favorably applied for minimum volume sample handling and fast detection response for sample analysis. Examples of uses for microchannel devices and systems can include, but are not limited to, biosensors, coupling waveguides, capillary electrophoresis chips, microreactors, polymerase chain reaction-chips, and solving mathematical problems.
However, manufacture of microchannel structures can be complicated and tedious. Also, manufacture methods may result in microchannel structures that have seams or include multiple members affixed (e.g., adhesive or bonding) together. These seams and junctions can cause imperfections in the microchannel that alter the dimensions of the conduit, which is unfavorable for micron scale applications. Also, these seams and junctions can be susceptible to failure during use.
An example of a conventional method for manufacturing microchannel systems is the use of lithography, in which three-dimensional channel patterns are first generated on a substrate using a series of processes, such as photo exposure, development, baking, etching, and the like, after which a microchannel is formed with one sidewall open so as to have a “U” like shape. The process for closing the microchannel so that only the entrance and exit of the microchannel is open can include aligning the microchannel structure with a flat substrate and then fusing or chemically bonding the microchannel structure with the flat substrate. Although current microchannel manufacturing techniques can provide microchannel structures on both stiff (e.g., glass and silicon) and soft (e.g., poly(dimethylsiloxane) or PDMS) materials, these structures have seams or junctions between different materials or structure portions. As such, these structures can have imperfections that are not favorable for many applications of microchannels due to the seams or junctions. For example, the methods produce microchannel structures that can have misalignment that results in unsuitable and varied dimensions and/or failure of the seal at the interface of two body members, which may result in leakage from the microchannel.